Dust collector



A ril 4, 1939. A. B. oseoon DUST COLLECTOR I Filed April 21, 1938 2Sheets-Sheet 1 @Wiiob 141 217111 15'. 0; 000

A. B. oseoon DUST COLLECTOR April 4', 1939.

2 Sheets-Sheet Filed April 21, 1938 59 15215 H-Ziamec 7 3. m

Patented A 2... ,4, 1939 UNITED STATES PATENT OFFlCE I "2,153,210 InU's'r connso'ron Arthur B. Osgood, Minneapolis, Minn.

Application April 21,

1 Claim.

' ductory comment. Stated in a general way the invention has for itsobjectsimplicity and low cost of construction, ready adaptability tovarious positions and conditions and increased efflcienc in thedustcollecting action.

,The construction and arrangement whereby the objects above generallystated are accomplished will be made clear and will be more apparentafter flrst'having described the invention in a commercial formillustrated in the accompanying drawings wherein like charactersindicate like parts throughout theseveral views. Referring to thedrawings:

Fig. 1 is a perspective view with parts broken away in sections showingthe improved dust collector; y

. Fig. 2 is a horizontal section taken on the line 2-2 of Fig. 1'showing only the parts on the said section line; Fig. 3 is a horizontalsection taken on the line 3-3 of Fig. 1 showing only the parts on orclosely adjacent to the said section line; and Fig. 4 is a horizontalsection taken on the line l-t of Fig. 1 showing only the partson'orclosely adjacent to the said section line.

The entrance chamber of the dust collector is iormed within acylindrical shell 5 which has a I as tangential air inlet spout 6 and anannular cover.

m the axis of which is concentric to the axis orjuie cylindrical shell5. The large upper edge of the conical shell 9 is co-incident with thelower edge of the shell 5 and may be rigidly secured thereto in variousways, but preferably is detachably seis cured thereto. .This'detachableconnection, as shown, is made by nut-equipped bolts l0 passed throughannular angle flanges ii and i2 riveted or otherwise rigidly secured tothe said shells 5 and t. The outer edge of the'annular cover plate so i,as shown, is clinched around an annular angle flange i3 bolted, rivetedor otherwise rigidly secured to the upper edge of the cylindrical shell5. Concentrically located within the cylindrical shell .5 is a stack M,the upper edge of which, as

55 shown, extends slightly above the flange 8 and is 1938, Serial No.203.278

there provided with an outwardly projecting annular angle flange I 8'.The extreme upper edge of the stack I4 is co-incident with thecylindrical walls of an inverted cup-shaped dome or bonnet it that has atangential outlet spout II. This dome or bonnet is rotativelyadjustablein respect to the'stack so that the spout I! can be set atrotative adjustment may be accomplished in different ways as by a.swivel, but as shown, the

any angle in respect to the intake spout 6. This I adjustment isaccomplished by providing the dome at its lower edge with an outstandingannular angle flange l8- that is adjustabiy but further feature thedepending portion of thestack is in the form of a downwardly detachablytapering truncated cone Ma, the surface of which is concentric to thesurrounding portion of the conical shell 9.

As a further and very highly important feature the main body portion ofthe stack is provided with tangential dust discharge passages which, aswill presently be noted, produces a skimming action of the dust from theair. The preferred way of accomplishing this is to form the body of thestack M of a plurality of cylindrical segments overlapping toformshallow skimmer passages or outlets Mb and spaced by tie block Horiveted to the overlapping sections. As shown, the body of the stack ismade up of four segments, but the number may be increased or decreased.Preferably the conical skirt or lower end portion Ma of the stack iscontinuous or unbroken. In practice the skimmer passages are generallyabout one-sixteenth of an inch in width but that dimension may be variedaccording to the size of the apparatus.

The conical shell 9, at its lower end, terminates inc.contracted-discharge spout 20 which may dead air space at the bottomthereof, thereis interposed a baffle in the form of a cone 2| that isconcentrically located within the shell 8. This conical baflie, at itsupper end, is shown as secured to an axial upwardly projecting stem 22which, as shown, is rigidly supported by cross passage is left incommunication between the upper portion of the shell 9 and thesubstantially deadair space 24, that is in direct communication withthedischarge spout 20.

In practice it has been found that dust will tend to adhere to andaccumulate on the interior of the lower portion of the conical shell 9.To prevent such accumulation, I provide a rotary cleaner, which in thepreferred arrangement illustrated, involvesa rotary vane in the form ofa flat bar 25, to the ends of which are attached loosely dependingscraper chains or cables 26. The operation of this cleaning device willbe described later on.

The operation of the device or apparatus in the air cleaning and dustcollecting operation is substantially as follows:

The dust laden air under pressure will be blown through the intake pipeor tube 6 and delivered tangentially into the cylindrical shell 5. Theair thus introduced under pressure will, under high velocity, be causedto travel against the interior of the cylindrical shell, partaking of aspiral movement with downward trend. After making several circuitsaround the interior of the shell 5, the dust laden air will be caused tocontinue a spiral downward travel against the interior of the conicalshell 9; and as the dust laden air progressively moves downward withinsaid conical shell its travel per feet per minute, while remainingapproximately constant, will increase I in the number of completeconvolutions that it be seen that air finds its only outlet as it isupdownward into the conical shell. Moreover, most -makes per minute.

noted spiral rotary movements of the dust laden- Of course, under theabove air, the dust or heavy particles will be caused to travel againstthe shells and will progressively move toward the bottom of the shell 8.c From theforegoing description of parts it wi wardly whirled throughthe stack and dome by the action of the tangential outlet spout 11through which it is discharged. The downwardly projecting cone Ila ofthe stack positively prevents any of the air from, changing its downwardcourse and movement into the stack until after it has passed below thecylindrical shell-and well of the dust laden air will be caused totravel against the interior of the shell 9 until it reaches the spacearound the bailie 2! which cuts off further downward travel of the airand causes the same, while continuing its rotation in the constantdirection, to partake of an upward trend into the stack. The major partof the dust,

in fact all of the heavier particles, will be precipitated from the airdownward into the dead air space 24 before the air takes its upwardspiral course; but some of the lighter dust will be carried by the airupward into the stack. As this air,

- with the remaining light dust, is caused by centrifugal force to clingagainst the interior of the stack, it will be repeatedly deliveredagainst the shallow skimming passages Ila which will cause the dust tobe discharged back'into the main annular channel formed between thestack and the cylindrical shell. In this way all, or practically all, ofthe dust carried upward by the air will be delivered back into the mainair stream for re-s'eparation. The skimming channels Ila are so shallowthat the outer passage of air therethrough with the dust will be veryslight. Substantially one hundred per cent clean air will reach the domel6 from which it will be discharged tangentially through the spout I1.

It will be noted, by reference particularly to Fig. 4, that theoverlapping of the segments of the stack and the arrangement of theskimming passages therein is such that the air delivered tangentiallyinto the cylindrical shell 5, through intake pipe 6, will cause the airto whirl in a counter-clockwise direction and produce more or the latterfree from accumulated dust.

In the structure described, the dome l6 constitutes an upward extensionof the stack which, for reasons described, is preferably made rotativelyadjustable. To secure the best results, the outlet tube i! should haveat least as great or preferably a little greater cross section and airconducting capacity than inlet tube 6.

In the above described preferred arrangement, the dome, the cylindricalshell, the conical shell, the stack and the battle have a common axis.That is, they are in concentric arrangement in respect to a common axis.

a. While] the preferred form has been described, it will, of course, beunderstood that various alterations and changes in the featuresdisclosed may be made within the scope of the invention herein describedand broadly claimed.

What I claim is:

A dust collector comprising a casing having annularly spaced inner andouter cylindrical walls connected by a substantially horizontal cover'ortop wall and providing therebetween an unrestricted annular passageway,said inner and outer walls being formed adjacent said top wall withtangentially disposed discharge and inlet openings respectively whichopenings communicylindrical wall whereby to provide an air outlet stackcentrally through said casing, and said stack being provided with a domethe side wall of which is a substantial continuation thereof a abovesaid top wall and having a tangential outlet leading therefrom over saidtop wall to cooperate with said tangential inlet in causing air undertreatment to whirl violently through said annular air passage and alsothroughout said central outlet stack, whereby dust entrained with theair in said central stack will be thrown against the inner wall of saidstack and expelled therethrough into the whirling incoming air stream insaid annular passageway for further separation therefrom.

. ARTHUR B. OSGOOD.

